Along with the popularity of voice software, it is becoming more accepted by most computer users, and has been an indispensable part in people's daily life gradually. The existing computer device often provides an option for choosing an audio input interface, which needs the user to manually switch to choose among different audio input interfaces, however, the switching method herein requires the user to manually try to choose each audio input interface one by one until a voice signal is heard, which is very inconvenient. Moreover, the user often makes misconnection due to not knowing the correct audio input interface, as a result, the correct voice input can not be acquired.